Pitcher plant inspires a paper-based water harvester
doi:10.1038/nindia.2020.191 Published online 31 December 2020
A printer paper coated with a sponge-like porous polymer material can harvest water from an artificial fog or vapour-laden air, a team of researchers has revealed1.
The polymer coat helps generate water-loving spots on the surface of the paper, which mimics the surface of an insect-eating pitcher plant, the researchers from the Indian Institute of Technology in Guwahati explain.
This technique could help harvest water from nature without the need for any cooling arrangement, the researchers say.
The IIT scientists designed a water-loving slippery liquid-infused porous (SLIP) surface using a polymer and a natural and edible oil on printer paper. They then tested the efficiency of this paper in harvesting water from an artificial fog or vapour-laden air.
They found that the specially designed water-loving surface facilitated a faster growth of water droplets, and rapid shedding of those droplets, compared with other nature-inspired interfaces.
The water-loving paper surface started shedding water droplets after an exposure of 107 seconds to an artificial fog. A slight modification of the pattern of the water-loving surface further accelerated the shedding of the water droplets, the researchers found.
The polymer coat on the paper remained intact even after being exposed to acidic and basic solutions, artificial seawater, river water and ultraviolet light for 30 days, the researchers say.
1. Maji, K. et al. Synergistic chemical pattern on hydrophilic slippery liquid infused porous surface (SLIPS) for water harvesting application J. Mater. Chem. A. 8, 25040-25046 (2020)